explain select ss_customer_sk ,sum(act_sales) sumsales from (select ss_item_sk ,ss_ticket_number ,ss_customer_sk ,case when sr_return_quantity is not null then (ss_quantity-sr_return_quantity)*ss_sales_price else (ss_quantity*ss_sales_price) end act_sales from store_sales left outer join store_returns on (store_returns.sr_item_sk = store_sales.ss_item_sk and store_returns.sr_ticket_number = store_sales.ss_ticket_number) ,reason where store_returns.sr_reason_sk = reason.r_reason_sk and r_reason_desc = 'Did not like the warranty') t group by ss_customer_sk order by sumsales, ss_customer_sk limit 100;
